/*
 * Copyright 2009-2015 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      https://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.springframework.security.kerberos.authentication;

import org.springframework.security.authentication.AuthenticationProvider;
import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
import org.springframework.security.core.Authentication;
import org.springframework.security.core.AuthenticationException;
import org.springframework.security.core.userdetails.UserDetails;
import org.springframework.security.core.userdetails.UserDetailsService;

/**
 * {@link AuthenticationProvider} for kerberos.
 *
 * @author Mike Wiesner
 * @author Bogdan Mustiata
 * @since 1.0
 */
public class KerberosAuthenticationProvider implements AuthenticationProvider {

    private KerberosClient kerberosClient;

    private UserDetailsService userDetailsService;

    @Override
    public Authentication authenticate(Authentication authentication) throws AuthenticationException {
		UsernamePasswordAuthenticationToken auth = (UsernamePasswordAuthenticationToken) authentication;
		JaasSubjectHolder subjectHolder = kerberosClient.login(auth.getName(), auth.getCredentials().toString());
		UserDetails userDetails = this.userDetailsService.loadUserByUsername(subjectHolder.getUsername());
		KerberosUsernamePasswordAuthenticationToken output = new KerberosUsernamePasswordAuthenticationToken(
                userDetails, auth.getCredentials(), userDetails.getAuthorities(), subjectHolder);
		output.setDetails(authentication.getDetails());
        return output;

    }

    @Override
    public boolean supports(Class<? extends Object> authentication) {
        return (UsernamePasswordAuthenticationToken.class.isAssignableFrom(authentication));
    }

    /**
     * Sets the kerberos client.
     *
     * @param kerberosClient the new kerberos client
     */
    public void setKerberosClient(KerberosClient kerberosClient) {
        this.kerberosClient = kerberosClient;
    }

    /**
     * Sets the user details service.
     *
     * @param detailsService the new user details service
     */
    public void setUserDetailsService(UserDetailsService detailsService) {
        this.userDetailsService = detailsService;
    }

}
